Combine participants and enrolled users list

NOTE: THIS PROJECT HAS NOT BEEN SUBMITTED FOR DEVELOPMENT.

Background
Nick Thompson asked if UCLA provided the code for this development work, should it be voted as successful, have a reduced estimate. In discussion in telegram, we (Martin, Damyon, Marina, Shannon) agreed on a 20% reduction to the $40,000 estimate.

The current code developed by UCLA has been provided, but Nick notes that they are working on making it a single git commit.

Task
I'm not sure what to do with this code, but perhaps review it now briefly, provide feedback here, and it can give a bit more clarity on code quality and something to work with.

Note: the project is likely to succeed for budget and vote reasons. Project voting deadline is 15 July 2016

More info
From Rex Lorenzo @ UCLA

Yes, we have code that we used to completely replace the Moodle code ....

I have attached the files that we placed using Moodle custom script mechanism: https://docs.moodle.org/dev/customscripts

It seems to work in Moodle 3.1, so it should be considered as a possible straightforward replacement with minor adjustments.